Film processing apparatus



June 12, 1945.

A. R. HANSEN FILM PROCESSING APPARATUS lFiled April 15A, 1943 June 12, 1945. A. R. HANSEN FILM PROCESSING APPARATUS 5 Sheets-Sheet 2 Filed April 15, 1943 June l2, 1945. A. R. HANSEN FILM PROCESSING APPARATUS 5 Sheets-Sheet I5 Filed April l5, 1943 IIIII June 12, 1945. A. R. HANSEN l 2,378,217

` FILM PROCESSING APPARATUS Filed April 15, 1943 5 Sheets-Sheet 4- o A 3y, v

MMV, 05M j :32%

June 12, 1945. A. R. HANSEN 2,378,217

FILM PROCESSING APPARATUS I l Filed April 15, 1943 5 Shee'S-Sheet 5 if Y arvzeys;

Patented June 12, 1945l UNITED STATES PATENT OFFICE 2,878,217 FILM PROCESSING APPARATUS Arthur R. Hansen, Chicago, Ill. Application April 15, 1943. Serial No. 483,124

('Cl. Sii-89)'A 14 Claims.

'I'his invention relates to improvements in a film processing apparatus, and in particular to a device by means of which photographic films may be automatically subjected to the successive steps of developing, washing, fixing and washing.

In developing an exposed nlm, it is first placed in a developing solution, then rinsed, then placed in a fixing solution, and then rinsed again. These steps are usually effected by manual operations. In my invention, I provide a series of tanks containing the desired solutions and washes, which tanks are positioned adjacent .one another in alignment. I preferably providea continuous conveyox` which operates at a constant speed and conveys the film through each of the tanks in succession, the length of time during which the illm is subjected to the actions of the various solutions being roughly dependent upon the length of the tank.

It is a primary object of my invention to provide in connection with such device, a means for transferring the film from one tank to another. It isl preferable that this transfer be effected quickly so that the small amount of developing or fixing solution which adheres to the surface of the film will not have an opportunity to react with the nlm to an extent which will affect the film in an undesirable manner.

It is a further object of my invention to provide a transferring means, such as that above indicated, which is intermittently operable, and to provide control means therefor which is responsive to the position of the film. That is, the transferring means operates only when a film has completed its-course of travel through one tank and is in position to be engaged by the transferring means and to be transferred to an adjacent tank. l

It is a further` objectvof my invention to provide means for co-ordinating the intermittent operation of the transferring means to the operation of the horizontal conveyor so that the former. between successive operations, will always remain in a position wherein a succeeding nlm will be engaged and transferred at the proper time.

A still further object is to provide novel transferring means in the form of an elevator, which not only elevates the lm so that its bottom edge will be clear of the wall of the tank, but also to control its descent into the succeeding tank.

A stili further object is to provide improved illm holding means which cooperates with the conveyor and the various transferring means.

' within the body I0, and

having a hinged wall 22.

Still another object is toV provide improved means to facilitate the positioning of the film holding means at a predetermined point on the conveyor whereby the time that the film is sub- .iected to the* developing solution may be regulated.

The invention herein described is shown as adapted for use with a photographic film or plate of substantial size. such as an X-ray film, although it will be understood that my invention is equally well adapted for processing films of other sizes. types or forms.

With reference now to the drawings in which like reference numerals represent like parts,

Fig. 1 is an elevation of a preferred embodiment of my invention. portions thereof being broken away for purposes of clarity;

Fig. 2 is an enlarged detailed view of the elevator driving and control mechanism; s

Fig. 3 is a detailed elevation, similar to Fig. 2. but showing certain parts in a changed position, and showing certain other parts which do not appear in Fig. 2;

Fig. 4 is an enlarged plan view of the timing selector bar;

Fig. 5 is a sectional elevation taken along line t-l of Fis. 6:

Fig. 6 is a section taken along line 6-6 of Fig. 5; and

Fig. 'l is a detailed view taken along line 1-1- of Fig. 1 showing the conveyor drive mechanism.

As shown in Fig. 1. the preferred embodiment of my invention herein disclosed comprises a body IIi which is mounted on legs I I. Along the upper edges of the body are conveyor chains I2 and Il, as shown more fully in Fig. 6. Disposed shown in dotted lines in Fig. '1, are a series of tanks, a developing tank Il. a washing tank I5, a fixing tank I8, and another washing tank Il. Mounted on the body I0 are elevator mechanisms designated generally by the reference numerals I8. I9 and 20. the elevator Il serving to transfer the iilm from the developing tank I4 to the washing tank I5, the elevator I9 serving as a transfer means between tanks Il and IB, and the elevator 2li serving as' transferring means between tanks I8 and I1.

The body III is provided with side walls 23 and J1, the former being hereinafter designated as the front wall and the latter as the rear wall, respectively. A housing 2i which encloses the drive and control mechanism for the elevators I8 and I9 is disposed on the front wall 23: this housing A similar housing 24,

.-having a hinged wall 2i is provided for the drive shown in Figs. 7 and 6, respectively.

and control mechanism for the elevator 28. Mounted at the lei't end of the machine is a housing 2l enclosing the drive mechanism for the conveyors i2 and I3. this mechanism being designated generally by the reference numeral 21. This mechanism includes a motor 28 which drives a sprocket wheel 28. A shaft 3,2A is provided with a sprocket wheel 3| and is driven from the sprocket wheel 23 by means of a chain III. The shaft 32 is provided with sprocket wheels 32a and 32h which engage and drive the conveyor chains I2 and I3, as shown in Fig. '7. A similar shaft 33 is provided at the right-hand end of the machine., this shaft having a sprocket wheel 34 for the conveyor chain I2, and a sprocket wheel 34a for the conveyor chain I3.

The shafts 32 and 33 are journalled at their front ends in a plate 35 which is mounted above the front wall 23. At their rear ends they are journalled in suitable brackets 38 and 38a as An inner front wall 38 is placed from the front wall 23 by means of a spacer 33, this construction providing a cavity 40 between the two, which may act as temperature insulation, or if desired may be illled with rock wool. A plate 4I is horizontally disposed'above the inner andfouter front'walls 38 and 23. on which plate the plate 35 rests. The

plate 4I may be suitably secured to the walls 23 and 38 by means of screws. A shown the walls 23 and 38 are made of wood, but other materials may be used if desired. Plate cured with respect to the horizontal plate 4I by means of a plurality ci. brackets 42. A channel 43 is carried on the brackets 42, and runs lengthwise of the machine and serves to carry the upper course of the conveyor chain I2. The lower course of the chain I2 rides on the horizontal plate 4I n The rear wall construction is similar to that described in respect to that of the front wall; there being a spaced inner wall 44 and a spacer 48 which forms a cavity 46 for purposes of insulation. A horizontal plate 41 is mounted on the upper edges of the inner and outer rear walls 44 and 31, respectively. and brackets 48 are mounted on the plate 41, which brackets carry a channel 48. The upper course of the conveyor chain I3 rides in the channel 43, and the lower course rides on the horizontal plate 41, this plate g being provided with a plurality of guides 58 to confine the lower portion of the conveyor chain tothe plate 41.

Angle irons I and 52 are mounted on the underside of the plates 4| and 41, respectively, being secured to such plate and to the outer, front and rear walls, respectively.

A similar. double wall construction is provided at the ends of the machine. As shown in Fig. 1, the right end of the machine comprises an outer end wall 84 and a spaced inner wall 5B. The left end wall construction is similar thereto but not shown. n

'I'he space between the inner side walls 38 and `ner walls to provide a surrounding chamber 3i in which water may circulate. Thus the tank I4 comprises a container 82 having a lining 63, the

vCII

is suitably se- I4 and between the inner end walls 55 is divided 'by means of spacers 1|, as shown wash tank I8 comprises .a container 34 having a lining 88, the iixlng tank I8 comprises a con? tainer il having a lining 81. and the w tank I I comprises a container 88 having a lining 8|. I have found that certain plastic compositions serve well as a lining. but if preferred porelain enamel ware. or other linings, may be use The body I8 ofthe apparatus is also provided with a bottom member 1li, and the bottom walls of cach of the containers 82, 84, 88 and 88 may preferably be spaced above the bottom member 18 in Fig. l with respect to the container 88. ,y

The chamber 3| provides a water jacket around ach of the containers in order that the temperature of the various solutions may be controlled. An inlet tor each water Jacket is provided in the form of a pipe 12 passing through the outer and inner rear walls 31 and 44, only one inlet being shown in Fig. 6. Pipe 12 and other inlet pipes are in communication with a supply pipe 13 which runs lthe length oi. the machine behind the outer rear wall 31. Outlets of similar construction are also provided, but not shown herein.

A pair of plates 14 and 1li is vertically mounted on the horizontal plate 4| 'by means of an angle iron 18. A similar pair of plates 1B and 11 is mounted on the horizontal plate 41 by means of an angle iron 18. The plates of each pair are held in spaced relationship with each other by spacers 8| and comprise the supporting structure of the elevator I8. The supporting structures of. the elevators I9 and 2li are identical thereto, and are indicated by the same reference numerals which are primed and double primed, respectively. for elevators I9 and 20, the same system being hereinafter used with respect to the remaining elements of the elevator structures and the drive and control mechanisms therefor.

A shaft 80 is .lournalled in plates ,15 and 1|i,` and extends through plates 14 and 15, the front end of the shaft 80 extending into the housing 2|. Sprocket wheels 88 and 89 are mounted on shaft 88 between plates 14 and 15 and between plates 18 and 11, respectively. A shaft 82 is journalled in plates 14 and 15 at a point near the top of said plates, this shaft carrying a sprocket wheel 83 positioned between the plates, and in alignment with the' sprocket wheel 88. A similar shaft 84 is provided at the top of the plates 13 and 11, and a sprocket wheel 85 is mounted on shaft 84. An elevator chain 36 runs over the sprocket wheels 88 and 83, and a similar elevator cha-in 81 runs over the sprocket wheels 89 and 38.

The housing 2|, into which the forward end of the shaft 80 extends, is formed in two parts. The lower part comprises a U-shaped strap 90 having bent over ends or flanges 83 by means of which this strap is secured to the underside of the angle iron 5I. 'I'he hinged outer wall 22 is secured to the strap 38 by means of hinges 8|. Similarly, withf respect to housing 24, the hinged wall 2B is secured to the strap 30" by means of hinges 3|". 'I'he upper portion of the housing 2| comprises a removable cover 82 whichv is bolted to the flanges 33 as shown in Figs. 1 and 6.

Disposed within the housing 2| are braise motors 84 and 34 for the elevators I8 and I3. Inasmuch as the mechanism for elevators I3 and 28 is identical to I8. only one of the motors and associated mechanism will hereinafter be mentioned. The motor is mounted on the strap 90 and is provided with suitable reduction gearswhich are disposed withthe mechanism for elevatorv in an extended -housing 35,.which is unitary with the motor 04. A sprocket wheel is driven by the motor 34, and meshes with a sprocket chain 31 which drives a sprocket 03 mounted on the forward end of shaft 30. When the motor cirmember |20 which is shownin Figs. 2 and 3, this displaceable member being mounted at the -front side-of the machine and\projecting into the cuit is closed, the motor, through the chain 31 will drive the shaft 30, which in turn will drive the elevator chains 30 and 31.

Timing selector bars |00 and IOI are suitably bolted to the underside of the channels 43 and 40 as shown in Fig. 6. These bars are generallyl of U-shape and are provided with a plur-ality of slots |02 in their top surface, these slots extending somewhat over into the connecting portion 'of the U-shaped member so as to make a slight depression, indicated by I02a, when the selector bar is viewed in side elevation as shown in Figs. 1 and 3. The top side portion of the U-shaped structure is provided with indicia |03. which are located on the tongues which are formed by adjacent slots |02. 'I'hese indicia indicate Vthe time in minutes which it takes forv the conveyor chain I2 to travel from a point directly beneath the corresponding slot to a'point adjacent to the elevator chain 86. The motor 28 drives the conveyor chain at a constant rate of speed. The construction of thetiming selector bar I 00 is substantially identical to the above` mentioned construction of the timing selector bar.

verse bar |01 as shown in Fig. e, to which arev secured vertical depending bars |03 and I 09. vA reinforcing transverse bar H0 serves to join the parts in a rigid structure. A depending member III is secured to the reinforcing transverse bar IIIi and is provided with clips II2 and |I3 which serve to hold ya film II4 in depending position therefrom.

In operation the upper transverse bar |01 of vthe film holder |00 rests in the depressed portion ycvf the links of the conveyor chains I2 and I3. As the conveyor chain moves from left to right, the film holder |03 will be carried by the chain through one of the tanks. When the film holder has reached the right-hand end of any of the tanks I4, I5 or I8, it will be in a position to be engaged by a rpair of the lugs |04, |05 and is lifted out of that particular tank and transferred into the next tank. As mentioned above, the time during which the film is subjected to the operation of the developing solution in tank I4 is predetermined by the position of the film holder whenit is initially put in the tank, and the determination of this position is facilitated by the timing selector bars |00 and IOI.

Means are provided to operaterthe elevators |5. I0 and 20 intermittently; that is, the operation of the motor 34 is controlled by the film `holder |00 so that the elevator chains 30 and 01 will start to move only after the holder has arrived at the end of the tank and is in a position to be engaged by the lugs' |04 and |05. These means further insure that the elevator will cease its operation when the film holder has been transferred to the next tank.`

Such control means include a displaceable [path ofthe front end of the bar I 01 of the illm holder |05. This displaceable member |20 is mounted on a lever I2I -by means of a. screw |22 in a manner to permit adjustment of the angular position of the displaceable member |20 with respect to the lever |2|. The displaceable member is provided with forwardly turned ears |23 and |24 through which adjusting screws |25 and |213 extend, the ends of the adjusting screws engaging a pin |21 which extends forwardly from an underlying portion |23 of the lever |2|. The displaceable member is provided with an arcuate slot |20 through which the pin |21 extends. It will be seen that the adjusting screw |25 may be loosened, and the adjusting screw |23 tightened by a corresponding amount which will cause the displaceable member to be shifted in a clockwise direction with respect to the position of the lever |2|. Thus the oper-ation of. the elevator will be delayed :or the reason that the displaceable member will not. be engaged by the film holder as soon as it would be as if suchy adjustment had not been made. Similarly, the parts may be adjusted to advance the action of the elevator.

The lever I2I is pivotally mounted on the plate by means of a screw |30. One end of the lever I2| is provided with a counterwelght I3I which is slidingly mounted on a bar |32 which is disposed parallel to the lever |2|. A set screw |33 provides means by which lthe position of the counterweight, and the effect thereof, may be adjusted.

A second lever |34 is pivotally mounted on a screw |35, the second lever carrying a mercury switch |30 which is connected in circuit with the motor 04 by means of a cable |31. The mercury switch |33 is mounted above the upper edge of a vertically disposed plate |38 by means of clips |40. The angular position of the plate and of the mercury switch is adjustable with respect to the position of the second lever |34 by means of a set screw |42 which takes into the second lever |34, and extends through an arcuate slot I4I in the plate |30, the head of the screw bearing against the plate |30. The left-hand-end of the plate |33 is pivoted on the lever |34. A link |44 connects the first lever |2I with the second lever |34, the link being associated with the respective levers by screws |45 and |40.

In operation it will be seen that as the "film holder is carried by the conveyor chains I2 and I3 to the right, just before the film holder reaches the end of the tank, it will engage the displaceable member |20 and rock the lever |2I in a clockwise direction, thereby rocking the second lever |34 in a. counterclockwise direction and tilting the mercury switch |36 so as to close the motor circuit. This will start the elevator chains 86 and 81 in motion, andthe film holder |00 will be engaged by lugs |04 and |05 and removed from tank I4 and transferred over to tank I5.

As shown in Figs. 5 and 6, slides |50 and ISI are secured to the inner surfaces of plates 15 and 10 respectively. These slides are merely strips of metal that are disposed at the right-hand edges of the plates 14 and 15 which will serve to disengage the bar |01 of the nlm holder |00 as it is descending. and to lift this bar clear of the lugs |04 and |05 of the elevator. Inasmuch as the conveyor chains |2 and I3 move at a much llower rate of speed than the elevator chains 00 and viewed in Figs. 2 and 3, is shaped so that when the parts are in closed circuit position, the lever |55 will be engaged by the iilm holder as it isv sliding down the slides |55.and The impact of the nlm holder on the lever |55 will serve to return the parts to their original open circuit position as shown in Fig. 2. The motor having stopped, the elevator will then remain stationary until the displaceable member |25 is engaged by another nlm holder.

A plate |52 is mounted Von the forward side oi' the elevator structural plate 15, the plate |52 having a bent-over ear |55 at its upper portion, through which an adjusting screw |55 extends. The adjusting screw |54 is; provided with a collar which serves to hold it in position on the ear |52, and the threaded portion of the adjusting screw takes into a bent-over ear |155 formed at the upper portion of a sliding plate |55. The vertically sliding plate |55 is provided with a vertically disposed slot |51, and is held in place against the plate |52 by means ci' a set screw |55. The vertically sliding plate is also provided with an ear |55 at its right-hand edge through which' ear extends an adjusting screw |55 which cooperates with the ear |55 of a horizontally sliding plate |5|. The hori-i zontally sliding plate is held in position against the vertically sliding plate |55 by means of a set screw |55 which extends through a horizontally disposed slot |52 in the horizontally sliding plate |5|. The lower edge oi the horizontally sliding plate |5| is provided with a bent-over portion |54 to which is secured a strip oi metal |55, on the right-hand portion of which is mounted a pair of contact strips |55 and |51 by means of a group of insulating blocks |55. The contact strips |55 and 51 are connected into the brake circuit of the brake motor 55 by means ci conductors which are contained in a cable |55.

It will be seen from Fig. 2 that as the film` holder |55 moves toward-the elevator chain 55 that it will not hit one of the lugs |54; in other words The operation of the elevator drive and control means is shown inlligs. 2 and il.v In Fig. 2 the position ot the nlm holder |55 is shown as resting on the conveyor chain |2, as the conveyor chain approaches the elevator chain 55. In order for the nlm holder |55 to move into a position wherein it will be engaged by one of the lugs |55 oi the elevator chain 55, it is necessary that the idisplaceable, member be engaged and dis- -placed by the iilm holder. The counterweight itibala'nces the system or levers, |2| and |25,

so that only a very slight force is required to move them from the position shown in. Fig. 2 to that shown in Iig. 3. Due to the factthat the slope of the depressed portion oi the links of the conveyor chain I2 is small, it will be seen that this counterbalancingf is ecessary. Otherwise the displaceable member 25 would not be displaced, but would only serve\to move the nlm holder backwardly with respect to the link at the conveyor chain on which it rests by gravity.

the elevator chain has been stopped in a position in which the lugs are clear of the path oi' the nlny holder. vIi the lug |55 were at a level where it would block further movement -of the film holder |55, it is clear that the displaceable member |25 would not. be displaced sufficiently to set Y the elevator chain in motion. This condition, however, is obviated by providing the contacts |55 and |51 which close the brake circuit of the brake motor 55, and consequently serve to prevent any overthrow of the amature oi' the motor. The position of the contacts |55 and |51 is determined by the adjusting screws |55 and |55 so that the motor will be braked at a time at which the path of the nlm holder |55 is not blocked by a lug |55. The contact member |55v extends into the path of the descending film holder |55 so that the brake circuit will be closed by the engagement of the nlm holder `with the contact member |55. Inasmuch as the elevator chain 55 travels at a fairly rapid rate, they interval between the closing of the brake circuit and the opening oi the motor circuit is so small that the armature will not havetime to get into motion again. The adjusting mechanism for the contacts, namely. plates |52, |55 andv |55, are preierably enclosed in a removable housing |15 as After the iilm holder |55 has arrived in the Position shown in Fig. 3, the motor circuit is closed and the elevator chain starts ,in motion.

The film holder will beengaged by the next succeeding lug |55. At this time, it will be noted. the remote end of the lever |55 has been kicked upwardly so that it projects above the conveyor chain I2. A stop pin |15 serves to limit the mction of the levers |2| and |55 into the closed circuitposition. l

After the tllm holderhas been carried upwardly by oneof the lugs l|55 to the top of the elevator, the iilm holder will begin to slide downwardly away from the lug by which it had been previously engaged, and into contact with the next preceding'lug. In order to minimize the eilect of the free movement of the film holder, and to prevent any rebound which might cause the film holder to bounce clear of the next preceding lug, spring members |12 and |15 are provided which, as shown in Figs. 1 and 6, will engage the film holder and serve to retard its motion. These spring members are mounted on a top cross meinber |15 which is secured at either end to the ele'- vator structural plates 15 and 11. o

As the illm holder again approaches the'horizontal conveyor chain |2, it will be disengaged from the lug |55 by means of the slide |55, after which it will slide downwardly and be positioned on the conveyor chain I2 at a point which'will be clear of the lugs |55. At substantially the same time the contacts |55 and |51 will be closed by the illm holder, thereby closing the brake circuit cf the motor and causing thewhole elevator mechanism to stop in a position wherein a suc.. ceedin'g nlm holder may later be engaged by one oi' the lugs |55. Immediately after the closing of the brake circuit, the nlm holder will engage the projecting remote end of the second lever |55, and cause it to be returned to the position shown in Fig. 2 wherein the motor circuit will be opened. The movement ot the lever system |2| and |55 into open circuit position is determined by the pivot |55', and a stop |1I' is provided for'the The free sliding movement of the nlm holder on the slides |55 and |5| permits an impact of the iilm holder on the lever- |55' ofv tank to the next tank.

' portio If desired, a backboard IBD may be provided at th rear end of the machine, above the body Ill, as shown in Fig. 1. Upon this backboard may be mounted a mixing -valve I 8|, together with a temperature indicator |82 and whatever automatic thermostatic control means may be desired. By means oi' the mixing valve IBI, the temperature of the water circulating through the chambers 8| may be controlled. It is preferable to maintain this temperature at 65 F. By means of the constant temperature water jacket 8|, the solutions in each of the tanks I4, I8, I6 and I1 will be maintained at the Aproper temperature.

The operation of my invention has scribed above in connection with the operation of -its component parts.4 After the tanks have been filled with rinsing water, developing and fixing solutions of the proper concentration, they may be brought to the proper temperature by manipulation of the mixing valve I8I. A counter |83 is provided to count the number of films processed in the machine, and this counter is at this time setto zero.

The apparatus may then be connected to a suitable source of electrical power by means of the cord |84, and the horizontal conveyors I2 and I8 are set into motion by operation of the switch |85. The films to be developed are mounted in film holders, and after the proper length of time z for processing in the developing solution had been determined, the films are successively placed upon the corresponding plates in the proper position on the conveyor chains I2 and I3, lthis position being determined by means of the timing selector preferably takes less than ten seconds. The time that the film is subjected to rinsing and fixing steps depends roughly on the lengths of the rinsing and fixing tanks.

As the film holder approaches the end of the second rinsing tank I'I, the film will be completely processed and the film holder may be lremoved by the operator.

If strips of iilrn are to be processed, the film holder |08 will be of somewhat different form,

but otherwisethe operation of the machine will be thesame. Mogon picture films can be developed in the apparatus herein shown and described by providing a holder which holds a reel, in which the successive convolutions of the motion picture films are spaced from one another by suillcient distance as to provide proper reaction with the various solutions.

Although I have shown but one preferred em- `been de- I corresponding positions for holding the opposite ends of said iilm holder against said chains, means for driving said elevator chains, and snubber means disposed near the top of said elevator chains for engaging said film holder as it begins to slide on said chains downwardly away from one of said lugs and to retard its motion as it moves into engagement with a preceding lug.

2. In a illm developing apparatus, aillm holder. mechanism to transfer a film holder from one tank to an adjacent tank comprising two elevator chains oppositely disposed at the sides of said tank, lugs carried by said elevator chains in spaced relationship and cooperating therewith for holding the opposite ends of said film holder as it is lifted clear o'f said first tank and lowered into said second tank, means for driving said elevator chains, and means for limiting the free movement of said nlm holder with respect to said bodiment of my invention, it will be understood A elevator chains as it changes its direction of motion.

3. In a film developing apparatus, means for transferring a film holder from one tank to an adjacent tank comprising a pair of elevator chains for engaging opposite ends of said film holder, driving means for said elevatorchains, displaceable means extending into .the path of said film -holder for controlling the starting of said elevator driving means, and means extending into the path of said film holder for stopping said elevator chains in a. predetermined position.

4. In a lm developing apparatus, means for transferring a film holder from one tank to an adjacent tank comprising a pair of elevator chains for engaging opposite ends of said fllm holder, driving means for said elevator chains, a displaceable member extendig into the path of said film holder for controlling the starting of said elevator driving means, means extending into the path of said film holder for stopping said driving means, and additional means extending into the path of said film holder for restoring said displaceable member to its initial position.

5.`In a developing apparatus having va series of tanks disposed in end to end relationship, means to cause a film holder to be moved through successive tanks, said means comprising a continuously operating horizontal conveyor running along the edges of said tanks, means comprising a pair of vertically disposed conveyors for engaging the opposite ends ofl a nlm holder as it reaches the end `of one of said tanks and for lifting said film holder clear of the end wall of said tank an'd for depositingsaid film holder on said horizontal conveyor in a position wherein said nlm holder will be submerged in an adjacent tank, a control member actuated by the movement of said film holder as it is moved by said horizontal conveyor into a position proximate to said vertical conveyor for starting said vertical conveyor in motion, means actuated by the motion of said film holder vas it leaves said vertical conveyor for causing said vertical conveyor to cease its operation, and additional means operated by the motion of said film holder as it leaves said vertical conveyor for restoring said control member to its original position.

6. .In a film developing apparatus, a transferring device for a horizontally moving film holder comprising elevator mechanism, driving means therefor, and means for controlling the operation of said driving means including a control member capable of assuming an elevator oper-- ating position and a non-operating position and sition, saidcontrol member having a portion which extends iiitotthe path of said nlm holder as it leaves said, elevator mechanism whereby it may be moved into its non-operating position to render said driving means inoperative at the conclusion of a transferring operation.

7. In a nlm developing apparatus, transferring meansI for a nlm holder comprising elevator mechanism, driving means therefor, a mercury switch for controlling the operation of said driving means, said mercury switch being mounted on a counterbalanced lever for rotation between two positions, a member extending into the path of said nlm holder and adapted to be displaced by the,horizontal motion of said nlm holder, said member being associated with said lever to rock the same into its closed circuit lposition, said counterbalanced lever when it is in its closed circuit position being constructed so that it will be engaged by said nlm holder, and means to disengage said nlm holder from said elevator mechanism and to permit it to drop into contact with said counterbalanced lever. whereby said lever will receive a blow of sufficient impact to cause it to return to its opencircuit position.

8. Film developing apparatus comprising two adjacent tanks, a nlm holder adapted to hold a nlm submerged in one of said tanks. conveyor means for movingsaid nlm holder from one end of one of said tanks toward the other tank. said conveyor being provided with a plurality of spaced positions' for holding a succession of nlm holders, a pair of elevator chains disposed .at ons end of said nrst-mentioned tank to transfer said nlm holderto said second tank, driving means for said conveyor to drive the same at a predetermined rate of speed, and control means for 'asvaaiv l 'circuit for said motor, contact means for said brake circuit biased to open circuit position and adapted to be actuated by the movement of a nlm holder to closed circuit position, a second contact means for said power circuit adapted to be actuated by the subsequent movement of s. nlm holder to open circuit position, and means for causing a nlm holder to fall freely in a path wherein it will successively actuate said first and second contact means whereby the time interval between actuation of said two contact means is insuilicieut to permit said brake motor to become operative before said power circuit is opened.

.11. In an apparatus of the class described, mechanism for' transferring a nlm holder from `one tank to an adjacent tank, said mechanism comprising an elevator chain having elevating lugs spaced thereon, a brake motor for driving said chain and having abrake circuit and a power Y circuit, a slide positioned adjacent to said elevator.

v chain to remove a nlm holder from engagement with one of said lugs during downward travel of the same, contact means in circuit with saidl brake circuit. said contact means extending into ends of which are adapted to rest on said conthe path of said nlm holder as it slides down said slide whereby said elevator chain is caused to stop at a predetermined position, and additional means extending into the path of said nlm holder forsubsequently opening said power circuit, said additional means being positioned close to said contact means whereby said motor circuit is opened before said motor again starts up.

l2. Film developing apparatus comprising a tank.l conveyor means running along the side Vedges thereof, driving means for said conveyor means. a nlm holder including a bar the opposite veyor means whereby a nlm is held submerged in said tank and carried toward one end thereof.

`40 means for removing scid` nlm holder from said causing operation of said elevator chains when a nlm holder is moved into a positionto be engaged by said elevator chains and for stopping said elevator chains in a position wherein a succeeding nlm holder can actuate said control means for initiating another cycle of operation.

9. Film developing apparatus comprising two adjacent tanks, a nlmholder adapted to hold a nim submerged in one of said tanks. conveyor means for moving said nlm holder from one end of one of said tank's toward the other end. said conveyor being provided with a plurality of spaced pomtions for holding a succession of nlm holders in predetermined spaced relationship, a pair of elevator chains disposed at one end of said nrst-mentioned tank to .transfer said nlm holders to said second tank. driving means for said conveyor to drive the same at a predetermined rate of speed. and control means for causing successive cycles ofoperations of said elevator drivingtlieseme,sbrakecireuitandapower'llliolcier tank when it reaches a predetermined position. and position determining means overlying said conveyor means comprising a slotted plate to prevent the placing of a vfilm holder on said con-` veyor means at a certain area, except in one of several predetermined positions denned by the slots in said plate which correspond to predetermined periods of time during which said nlm will be maintained submerged in said tank prior to its removal therefrom..

i3. In a nlm developing apparatus, a tank, a

conveyor, pair of parallel chains associated therewith, a nlm holder including a bar adapted to rest on said conveyorchains. and positioning means to facilitate the initial positioning of said bar on said conveyor chains in perpendicular relationship. said means comprising a plate disposed above each of said chains and each provided with a plurality of slots therein which are of a width sufficient to permit the insertion of said bar therethrough, said slots-being perpendicular to said chains and the slots of one of said plates being oppositely disposed to the slots of the other. k

14. Developing apparatus comprising aseries of tanks disposed in longitudinal alignment. conveyor means running along the upper edles thereof, a' nlm holder adapted to be engaged by said conveyor and to hold a nlm submerged in 4one of said tanks as it travels from one end to the other end of said tank, mechanism to transfer said nlm` holder from one tank to an adjacent tank comprising means to lift said nlm holder from said conveyor and to deposit said nlm on said conveyor in an advanced position wherein said nlm is submerged in an adjacent tank, and control means for operating said transfer mechanism in a separate cycle of operation for each film holder transferred and independently of the operation of said conveyor means. said control means including meansactuated upon engagement by said film holder when `it reaches a predetermined position at the end of said first-mentioned tank to initiate the cycle of operation of said transfer mechanism, and means actuated upon engagement by said lm holder as 5f it is deposited on said conveyor in said advanced 'M position to terminate said cycle of operation.

ARTHUR R. HANSEN. 

